/*
 * Copyright (c) 1989, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Guido van Rossum.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* OpenBSD: fnmatch.c,v 1.6 1998/03/19 00:29:59 millert */

/*
 * Function fnmatch() as specified in POSIX 1003.2-1992, section B.6.
 * Compares a filename or pathname to a pattern.
 */

/* Define SYS to use the system fnmatch() rather than ours */
/* #define SYS 1 */

#include "include/susan.h"
#ifdef SYS
#include <fnmatch.h>
#else
#include "fnmatch.h"
#endif

#undef EOS
#define EOS '\0'

#define RANGE_MATCH 1
#define RANGE_NOMATCH 0
#define RANGE_ERROR (-1)

/* Limit of recursion during matching attempts. */
#define FNM_MAX_RECUR 64

#define ISSET(x, y) ((x) & (y))
#define FOLD(c) ((flags & FNM_CASEFOLD) && B_ISUPPER(c) ? tolower(c) : (c))

static int Rangematch(const char*, char, int, char**);
static int r_fnmatch(const char*, const char*, int, int);

#ifdef SYS
int xfnmatch(const char* pattern, const char* string, int flags)
#else
int fnmatch(const char* pattern, const char* string, int flags)
#endif
{
  int e;

  e = r_fnmatch(pattern, string, flags, FNM_MAX_RECUR);
  if (e == -1) { /* Too much recursion */
    e = FNM_NOMATCH;
  }
  return (e);
}

static int r_fnmatch(const char* pattern,
                     const char* string,
                     int flags,
                     int recur)
{
  const char* stringstart;
  char* newp;
  char c, test;
  int e;

  if (recur-- <= 0) { return (-1); }

  stringstart = string;
  for (;;) {
    switch (c = *pattern++) {
      case EOS:
        if (ISSET(flags, FNM_LEADING_DIR) && IsPathSeparator(*string))
          return (0);
        return (*string == EOS ? 0 : FNM_NOMATCH);
      case '?':
        if (*string == EOS) return (FNM_NOMATCH);
        if (IsPathSeparator(*string) && ISSET(flags, FNM_PATHNAME))
          return (FNM_NOMATCH);
        if (*string == '.' && ISSET(flags, FNM_PERIOD) &&
            (string == stringstart ||
             (ISSET(flags, FNM_PATHNAME) && IsPathSeparator(*(string - 1)))))
          return (FNM_NOMATCH);
        ++string;
        break;
      case '*':
        c = *pattern;
        /* Collapse multiple stars. */
        while (c == '*') { c = *++pattern; }

        if (*string == '.' && ISSET(flags, FNM_PERIOD) &&
            (string == stringstart ||
             (ISSET(flags, FNM_PATHNAME) && IsPathSeparator(*(string - 1))))) {
          return (FNM_NOMATCH);
        }

        /* Optimize for pattern with * at end or before /. */
        if (c == EOS) {
          if (ISSET(flags, FNM_PATHNAME)) {
            return (ISSET(flags, FNM_LEADING_DIR) || strchr(string, '/') == NULL
                        ? 0
                        : FNM_NOMATCH);
          } else {
            return (0);
          }
        } else if (IsPathSeparator(c) && ISSET(flags, FNM_PATHNAME)) {
          if ((string = strchr(string, '/')) == NULL) return (FNM_NOMATCH);
          break;
        }

        /* General case, use recursion. */
        while ((test = *string) != EOS) {
          e = r_fnmatch(pattern, string, flags & ~FNM_PERIOD, recur);
          if (e != FNM_NOMATCH) { /* can be NOMATCH, -1 or MATCH */
            return (e);
          }
          if (test == '/' && ISSET(flags, FNM_PATHNAME)) { break; }
          ++string;
        }
        return (FNM_NOMATCH);
      case '[':
        if (*string == EOS) return (FNM_NOMATCH);
        if (IsPathSeparator(*string) && ISSET(flags, FNM_PATHNAME))
          return (FNM_NOMATCH);
        if (*string == '.' && ISSET(flags, FNM_PERIOD) &&
            (string == stringstart ||
             (ISSET(flags, FNM_PATHNAME) && IsPathSeparator(*(string - 1)))))
          return (FNM_NOMATCH);

        switch (Rangematch(pattern, *string, flags, &newp)) {
          case RANGE_ERROR:
            /* not a good range, treat as normal text */
            goto normal;
          case RANGE_MATCH:
            pattern = newp;
            break;
          case RANGE_NOMATCH:
            return (FNM_NOMATCH);
        }
        ++string;
        break;

      case '\\':
        if (!ISSET(flags, FNM_NOESCAPE)) {
          if ((c = *pattern++) == EOS) {
            c = '\\';
            --pattern;
          }
        }
        /* FALLTHROUGH */
      default:
      normal:
        if (FOLD(c) != FOLD(*string)) { return (FNM_NOMATCH); }
        ++string;
        break;
    }
  }
  /* NOTREACHED */
}

static int Rangematch(const char* pattern, char test, int flags, char** newp)
{
  int negate, ok;
  char c, c2;

  /*
   * A bracket expression starting with an unquoted circumflex
   * character produces unspecified results (IEEE 1003.2-1992,
   * 3.13.2).  This implementation treats it like '!', for
   * consistency with the regular expression syntax.
   * J.T. Conklin (conklin@ngai.kaleida.com)
   */
  if ((negate = (*pattern == '!' || *pattern == '^'))) ++pattern;

  test = FOLD(test);

  /*
   * A right bracket shall lose its special meaning and represent
   * itself in a bracket expression if it occurs first in the list.
   * -- POSIX.2 2.8.3.2
   */
  ok = 0;
  c = *pattern++;
  do {
    if (c == '\\' && !ISSET(flags, FNM_NOESCAPE)) c = *pattern++;
    if (c == EOS) return (RANGE_ERROR);
    if (c == '/' && ISSET(flags, FNM_PATHNAME)) return (RANGE_NOMATCH);
    c = FOLD(c);
    if (*pattern == '-' && (c2 = *(pattern + 1)) != EOS && c2 != ']') {
      pattern += 2;
      if (c2 == '\\' && !ISSET(flags, FNM_NOESCAPE)) c2 = *pattern++;
      if (c2 == EOS) return (RANGE_ERROR);
      c2 = FOLD(c2);
      if (c <= test && test <= c2) ok = 1;
    } else if (c == test)
      ok = 1;
  } while ((c = *pattern++) != ']');

  *newp = (char*)pattern;
  return (ok == negate ? RANGE_NOMATCH : RANGE_MATCH);
}
